Lubricating arrangement for high speed spindles



United States Patent O i LUBRICATING ARRANGEMENT FOR HIGH SPEED SPINDLES Adolf Roesch, Pforzheim, and Just Sohlemann, Schonaich, Kreis Boblingen, Germany Application April 30, 1956, Serial No. 581,787 7 Claims priority, application Germany April 30, 12855 1 Claims. (Cl. 308-187) The present invention relates to high speed spindle assemblies.

In certain types of devices such as certain types of grinding machines, for example, there are spindles which rotate at extremely high speeds which may exceed, for example, 100,000 revolutions per minute. When an assembly includes a spindle which rotates at such an extremely high speed certain problems are involved in providing lubrication. This is particularly true where such a spindle is vertically arranged because then it is not possible to have all of the moving parts located at positions where oil from an oil bath may be conveniently delivered thereto. Thus, where such a spindle is vertically arranged an oil bath may be located very easily adjacent the lower end of the spindle, but it is not a simple matter to deliver oil in the desired manner to the upper portion of the spindle and the moving parts associated with this upper portion of the spindle.

One of the objects of the present invention is to provide a lubricating arrangement which is capable of efficiently lubricating a high speed spindle assembly of the above type even if the spindle is vertically arranged.

Another object of the present invention is to provide such a lubricating arrangement with a means for continually delivering a desirable amount .of lubricant to the moving parts of the assembly.

A further object of the present invention is to provide a lubricating arrangement of the above type with a selfcleaning means for throttling the oil or other lubricant delivered by a pump so that the oil or other lubricant which is delivered to the moving parts is not excessive in amount and so that the throttling means cannot become clogged.

An additional object of the present invention is to provide a lubricating arrangement of the above type with an oil or other lubricant pump assembly which requires no special drive means and which is characterized by an extremely simple construction.

Still another object of the present invention is to provide a lubricating arrangement of the above type with a means for centrifugally distributing the lubricant to the moving parts without requiring any special parts or drives to form such a centrifugal distributing means.

Also, it is an object of the present invention to provide a structure capable of accomplishing all of the above objects and at the same time being characterized by extreme simplicity and reliability of operation as well as by its compactness and ruggedness.

With the above objects in view the present invention mainly consists of a lubricating arrangement for a high speed spindle assembly, this lubricating arrangement including an elongated hollow housing and an elongated spindle extending into said housing. A first set of rollers of a diameter greater than said spindle are distributed about and engage the same, and a second set of rollers also of a diameter greater than said spindle and being axially spaced from the first set of rollers are also distrib uted about and engage the spindle. A support means supports the rollers for respective rotation about axes parallel to the spindle, so that when the rollers are driven the spindle rotates at a speed higher than that of the rollers. A reservoir is located in the housing for containing a lubricant, and a shaft is fixed to one of the rollers and extends into the reservoir so that this shaft rotates with the roller to which it is fixed. An impeller means is located in the reservoir and fixed to the shaft for rotation therewith, and a pump housing is located in the reservoir and cooperates with the impeller means for forming a pump therewith. This pump housing is formed with a suction inlet which communicates with the reservoir to receive lubricant therefrom, and this pump housing also has a pressure outlet. A conduit means communicates with the pressure outlet of the pump housing and leads therefrom to. regions respectively located adjacent the sets of rollers for delivering to the latter lubricant received from the pump.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. lis a sectional elevational view of a lubricating arrangement according to the present invention shown in association with a high speed spindle assembly, the section of Fig. 1 being taken along a central plane through the assembly;

Fig. 2 is a sectional elevational view on an enlarged scale of a pump structure forming part of the assembly walls 2 and 3 are fixed to the opposite ends of the housing 1 as by being screwed thereon, so that the housing 1 together with its end walls 2 and 3 form a closed chamber. An elongated spindle 4 extends through the wall 2 into the interior of the housing 1 and is coaxial with the latter. A first set of three rollers 5-7 are distributed about and engage the spindle 4 adjacent the bottom end of the housing 1. A second set of three rollers 810 are distributed about and engage the spindle 4 adjacent its top free end. The rollers 8-10 are respectively aligned with the rollers 5-7, and each pair of aligned rollers is interconnected by an elongated rod. Thus, the

rod 11 interconnects the rollers 5 and 8, while the rod j 13 interconnects the rollers 7 and 10. The roller 9 and the unillustrated roller 6 are interconnected by the rod 'j 12 which appears in Fig. 3.

A transverse wall 14 is fixed in the interior, of the housing- 1 in any suitable way against axial or rotational f movement, and a similar transverse wall 15 is fixed in the same way in the interior of the housing 1 adjacent to the end wall 3 thereof. The walls 14, 15 are fixed by screws 37 pressing them against 'a'snap spring 38 provided in a groove of the casing 1. The rod members 1113 have Patented Oct. 22, 1957 15 together with the bearings 17 form a support means for supporting the rollers for respective rotation about axes parallel to the spindle" 4. The portions of rods 1 1 13 which extend thr oughjhe transversewall .15 ex-. tend also through the' wall'3 tegrneextenor of the housing 1 in a fiuid-tight.nianner.,, Thus, as isshown inFi'g; l, the elongated free end portion of rod, 11 which extends through the wall 3 is located in a fiuid-tightnianrfer'yvith-.

in a sleeve which is in turn engaged by a sealing" ring 19 which thus allows the rod 11 to pass through the wall 3 in a fluid-tight manner. The same arrangement is provided for the rods 12 and 13. At their free ends which are located outside of the housing 1 extending beyond the end wall 3 thereof, the rods 11-13 fixedly carry a plurality of pulleys 20, respectively, and a suitable belt cooperates with these pulleys to drive the rollers. One belt may pass about and engage all of the pulleys 21 The spindle 4 extends in a fluid-tight manner through the end wall 2 of the housing 1, and a sealing ring 21 made of a relatively soft material in the same way as the sealing ring 19 engages the spindle 4 to allow the latter to rotate in a fluid tight manner with respect to the wall 2.

The rollers -10 press against the spindle 4 to impart rotation to the latter, and the spindle 4 is provided with portions of reduced cross section engaged by these rollers. The spindle 4 is provided with flared shoulders 22 which are preferably concave and which engage correspondingly shaped convex annular edges of the rollers to cooperate with the latter.

The transverse wall 14- defines with the wall 2 of the housing 1 a reservoir 23 adapted to contain a liquid lubricant such as any suitable oil. The bottom end of the rod 11 which extends through the lower bearing 17 shown in Fig. l is elongated to form a shaft 24 which extends into the reservoir 23. The reservoir 23 is filled and emptied by means of an opening in the casing 1 closed by a screw 36. The walls 14, have discharge openings 39. The bottom'free end portion of the shaft 24, as viewed in Fig. 1, is formed with a helical groove 25, and this helically grooved portion of the shaft 24 forms an impeller means which acts as an impeller of a pump. A pump housing which cooperates with this impeller means is formed by a simple sleeve 26 into which the shaft 24 extends and which cooperates with the shaft 24 in the same way as a bearing sleeve. As is indicated in Fig. l, the bearing 17 through which the shaft 24 passes is prevented from moving downwardly by, a snap ring located in a suitable groove formed in the plate 14, and an annular dished spring engages thissnap ring and engages a shoulder formed inthe top face of the sleeve 26, as viewed in Fig. l, to urge this sleeve downwardly against the end wall 2 of the housing 1, so that the sleeve 26 engages the end wall 2 in a fluid-tight manner. This sleeve 26 which forms the pump housing and which co operates with the impeller means to form a pump therewith is formed with a suction inlet 27, and it will be noted that this suction inlet 27 is in the form of a radial opening formed in the sleeve 26 and located directly next to the wall in alignment with the gap between the wall 2 and the free end of the shaft 24. A conduit 28 communicates with the inlet 27 and at its right free end, as viewed in Fig. l, is opened and communicates with the liquid in the reservoir 23, this conduit 28 simply extending along and engaging the wall 2. The sleeve 26 is formed also with a pressure outlet, and this pressure outlet takes the form of a pair of radial bores formed in the sleeve 26 and communicating with conduits 29 and 30.

The conduit 29 passes upwardly, as viewed in Fig. 1,

through'suitable bores formed in the transverse walls 14 and 15 to the space between the latter and the wall 3, and

leads into a recess 32 formed in the end face of the free end portion of the spindle 4. It will be noted that this recess 32 is of a substantially conical cofiguration, and the rotating spindle 4 enables its end portion provided with recess 32 to act as a centrifugal distributing means for centrifugally distributing the' lubricant delivered to the recess 32. 7

The conduit 30 communicates with a passage 33 formed 0 in the transverse wall 14, and this passage 33 has an outlet end communicating with the axial bore of the wall 14 through which the spindle 4 passes. This spindle 4 is formed opposite the outlet end of the passage 33 with a frustoc onical portion 34 which forms a centrifugal distributing means in the form of a spray ring for centrifugally spraying the oil received from the passage 33. It will be noted that the frustoconical portion 34 of the spindle 4 is located with clearance in the axial bore of the wall 1d, so that the oil may move outwardly away from the centrifugal distributing means 34 into the space between the wall 14 and the rollers 5-7. The part of the spindle d which is located directly below the frustoconical portion 34 thereof rotatably engages the wall 14 in a fluid-tight manner so as to seal the reservoir 23 from the interior portion of the housing 1 which is located on the opposite side of the wall 14 at the axial bore of the latter.

When it is remembered that the spindle 4 rotates at speeds greater than 100,000 revolutions per minute and that the rollers 510 rotate at speeds greater than 30,000 revolutions per minute, then it is evident that the impeller formed by the helically grooved portion 25 of the shaft 24 is capable of pumping more than enough lubricant for lubricating the entire assembly. The lubricant in the reservoir 23 is sucked into the interior of the housing 25 through the inlet 27 and is then pumped upwardly to the discharge conduits 29 and 30 by the helically grooved portion 25 of the shaft 24 which turns together with the roller 5. The lubricant delivered from the conduits 29 .and 30 to the spindle 4 in the region of the rollers 510 reaching the spray ring 34 is centrifugally distributed into then the conduit 29 moves downwardly back through the the space between wall 14 and rollers 57 to lubricate the latter as well as the bearings 17 associated therewith.

Because the above described pump is capable of delivering far more than the amount of oil or other lubricant required for efiicientlubrication of the parts, a throttling means is provided in the path along which the oil flows in order to deliver from the conduits 29 and 30 only a fraction of the amount of lubricant which the pump is capable of delivering. As may be seen particularly from Fig. 2, the throttling means of the present invention takes the form of the'sleeve portion of housing 26 which extends upwardly beyond the helical groove 25 to the discharge conduits 29 and 30.. With the arrangement of the invention the lubricant must move from the groove 25 to the outlets 29 and 30, and in so doing it must pass through the very small clearance which is provided between the shaft 24 and the sleeve 26, and this small clearance throttles the flow of lubricant so that a continuous, uninterrupted, steady supply of lubricant is provided to the rotating parts in an amount which is not at all too great. Although different types of throttling means could be used, the throttling means of the invention which is has no pertinence to the present invention and is therefore not described.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of high speed spindle assemblies differing from the types described above.

While the invention has been illustrated and described as embodied in lubricating arrangement for a high speed spindle assembly, it is not intended to be limited to the details shown, since various modifications and structural changes may be made Without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applyin current knowledge readily adapt it for various application Without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A lubricating arrangement for a high speed spindle assembly, comprising, in combination, a hollow housing; an elongated spindle extending into said housing; a first set of rollers of a greater diameter than said spindle distributed about and engaging the same; a second set of rollers of a greater diameter than said spindle axially spaced from said first set of rollers and also distributed about and engaging said spindle; support means carried by said housing and supporting said first and second sets of rollers for respective rotation about axes parallel to said spindle, so that when said rollers are driven the spindle will rotate at a speed greater than that of said rollers; a reservoir located in said housing and adapted to contain a liquid lubricant; a shaft fixed to one of said rollers for rotation therewith and extending into said reservoir; impeller means fixed to said shaft in said reservoir for rotation with said shaft; a pump housing located in said reservoir and cooperating with said impeller means for forming a pump therewith, said pump housing having a suction side communicating with the interior of said reservoir and a pressure side; a pair of centrifugal distributing means respectively located in the region of said sets of rollers for centrifugally distributing lubricant to said sets of rollers and said spindle; and conduit means leading from the pressure side of said pump housing to said pair of centrifugal distributing means for delivering lubricant thereto.

2. A lubricating arrangement for a high speed spindle assembly, comprising, in combination, a hollow housing; an elongated spindle extending into said housing; a first set of rollers of a greater diameter than said spindle distributed about and engaging the same; a second set of rollers of a greater diameter than said spindle axially spaced from said first set of rollers and also distributed about and engaging said spindle; support means carried by said housing and supporting said first and second sets of rollers for respective rotation about axes parallel to said spindle, so that when said rollers are driven the spindle will rotate at a speed greater than that of said rollers; a reservoir located in said housing and adapted to contain a liquid lubricant; a shaft fixed to one of said rollers for rotation therewith and extending into said reservoir; impeller means fixed to said shaft in said reservoir for rotation with said shaft; a pump housing located in said reservoir and cooperating with said impeller means for forming a pump therewith, said pump housing having a suction side communicating with the interior of said reservoir and a pressure side; a pair of centrifugal distributing means connected to said spindle in the regions where said sets of rollers are located, respectively, for centrifugally distributing lubricant to said rollers and spindle; and conduit means leading from the pressure side of said pump housing to said pair of centrifugal distributing means for delivering lubricant to the latter.

3. A lubricating arrangement for a high speed spindle assembly, comprising, in combination, an elongated hollow housing; an elongated spindle extending into said housing; a first set of rollers of a diameter greater than said spindle distributed about and engaging the latter; a second set of rollers of a diameter greater than said spindle axially spaced from said first set of rollers and also being distributed about and engaging said spindle; support means supporting said rollers for rotation about axes, respectively, parallel to said spindle so that when said rollers are driven said spindle rotates at a speed higher than that of said rollers; a reservoir located in said housing and adapted to contain a liquid lubricant; a shaft fixed to .one of said rollers for rotation therewith and extending into said reservoir, said shaft having in said reservoir an elongated portion formed with a helical groove and said helically grooved portion of said shaft acting as a pump impeller; a pump housing located in said reservoir and cooperating With said impeller to form a pump therewith, said pump housing having a suction inlet communicating with the interior of said reservoir and located at one side of said helically grooved portion of said shaft and said pump housing having a sleeve portion engaging said shaft beyond said helical groove thereof and formng the pressure outlet of the pump, said sleeve portion of said pump housing being formed with a passage means through which the lubricant is discharged under pressure, the clearance between the shaft and said sleeve portion of said pump housing located beyond said helical groove throttling the flow of lubricant to reduce the amount of lubricant deliveredby the pump to a fraction of the amount which it is capable of delivering; and conduit means communicating with said passage means for leading lubricant under pressure from said pump respectively to regions Where said sets of rollers are located for delivering lubricant to the latter and said spindle.

4. A lubricating arrangement for a high speed spindle assembly, comprising, in combination, an elongated hollow housing; an elongated spindle extending into said housing; a first set of rollers of a diameter greater than said spindle distributed about and engaging the latter; a second set of rollers of a diameter greater than said spindle axially spaced from said first set of rollers and also being distributed about and engaging said spindle; support means supporting said rollers for rotation about axes respectively, parallel to said spindle so that when said rollers are driven said spindle rotates at a speed higher than that of said rollers; a reservoir located in said housing and adapted to contain a liquid lubricant; a shaft fixed to one of said rollers for rotation therewith and extending into said. reservoir, said shaft having in said reservoir an elongated portion formed with a helical groove and said helically grooved portion of said shaft acting as a pump impeller; a sleeve located in said reservoir and into which said shaft turnably extends so that said sleeve acts as a bearing for said shaft, said sleeve covering and extending beyond said helically grooved portion of said shaft to cooperate with said shaft portion to form a pump therewith, said sleeve being formed with a pump inlet at one end of the helically grooved portion of said shaft and being formed beyond an opposite end of said helically grooved portion of said shaft with pas sage means acting as a pump outlet; spring means engaging said sleeve and urging the same against a wall portion of said housing which defines part of said reservoir into fluid-tight engagement with said wall portion; and conduit means communicating with said passage means and leading therefrom respectively to regions adjacent said sets of rollers for supplying lubricant to the latter and said spindle.

5. A lubricating arrangement for a high speed spindle assembly, comprising, in combination, a hollow housing; an elongated spindle extending into said housing; a first set of rollers of a greater diameter than said spindle distributed about and engaging the same; a second set of rollers of a greater diameter than said spindle axially spaced from said first set of rollers and also distributed about and engaging said spindle; support means carried by said housing and supporting said first and second sets of rollers for respective rotation about axes parallel to said spindle, so that when said rollers are driven the spindle will rotate at a speed greater than that of said rollers; a reservoir located in said housing and adapted to contain a liquid lubricant; a shaft fixed to one of said rollers for rotation therewith and extending into said reservoir; impeller means fixed to said shaft in said reservoir for rotation with said shaft; a pump housing located in said reservoir and cooperating with said impeller means for forming a pump therewith, said pump housing having a suction side communicating with the interior of said reservoir and a pressure side; a pair of centrifugal distributing means respectively located in the region of said sets of rollers for centrifugally distributing lubricant to said sets of rollers and said spindle, one of said centrifugal' distributing means being in the form of an end portion of said spindle which is formed with a recess and the other of said centrifugal distributing means being in the form of a spray ring portion fixed to said spindle for rotation therewith; and conduit means leading from the pressure side of said pump to said recess and spray ring portion for delivernig lubricant thereto to be distributed to said rollers and spindle.

6. A lubricating arrangement for a high speed spindle assembly comprising, in combination, an enlongated hollow housing; an elongated spindle extending into said housing, said spindle having in said housing a free end portion formed in an end face thereof with a recess and said spindle having axially spaced from said recess a portion of substantially frustoconical configuration which acts as a spray ring; a first set of rollers of a diameter greater than that of said spnidle distributed about and engaging the latter adjacent said free end portion thereof;'a second set of rollers of a diameter greater than that of said spindle distributed about and engaging the latter adjacent said frustoconical portion thereof; support means located in said housing for supporting said rollers for rotation respectively about axes parallel to said spindle so'that when said rollers are driven said spindle rotates at a speed higher than that of said rollers; a reservoir for a liquid lubricant located in said housing a shaft fixed to one of said rollers and extending into said reservoir; impeller means fixed to said shaft for rotation therewith and located in said reservoir; a pump housing also located in said reservoir and cooperating with said impeller means for forming a pump therewith, said pump housing having a suction inlet communicating with said reservoir and a pressure outlet; and conduit means leading from said pressure outlet respectively to regions adjacent said recess and frustoconical portion of said spindle for delivering lubricant to said recess and frustoconical portion so that.

the lubricant will be centrifugally distributed from said 7 recess and said frustoconical portion of said spindle to said rollers and spindle for lubricating the latter.

7. A lubricating arrangement for a high speed spindle housing, said spindle having in said housing a free end formed with a recess in the end face of said spindle at said free end thereof-and said spindle having a frustoconical portion axially spaced from said free end thereof and forming a spray ring; a first set of rollers of a diameter greater than said spindle distributed about and engaging the latter adjacent said free end thereof; a second set of rollers of diameters respectively equal to those of said first set of rollers axially spaced from the latter and be ing distributed about and engaging said spindle adjacent said frustoconical portion thereof, said second set of rollers being equal in number to said first set of rollers and the rollers of said second set being respectively aligned with therollers of said first set so that said first and second sets of rollers form pairs of aligned rollers; a plurality of elongated rods extending parallel to said spindle and respectively interconnecting each pair of aligned rollers; support means located in said housing and supporting said rods and said rollers therewith for respective rotation about axes parallel to said spindle, one i of said rods having an elongated shaft portion extending beyond one .of the rollers fixed thereto; a reservoir located in said housing for containing a liquid lubricant,

said elongated shaft portion of said one rod extending References Cited in the file of this patent UNITED STATES PATENTS 2,635,198 Wieseman Apr. 14, 1953 FOREIGN PATENTS 648,263 France Aug. 13, 1928 246,064 Switzerland Aug. 16, 1947 

